Animation Nodes - Extract single object from group to perform independent translations
Let us first simply your node tree into something that is more efficient. Since you are not using matrices and setting the rotation and locations independently, we can use a vectorized Object Transforms Output node to do both. Moreover, since you are only offsetting the location component of the matrices, we can use a vectorized Offset Vector instead. So our node tree reduces to:



If you want to edit the translation of each object independently, you can input the custom translation vectors into the offset input, for instance, we can translate the first and thrid objects in the opposite direction as follows:



What if you want to animate the rotation? Simply offset zero vectors, convert them to eulers and set them to the objects:



Want to implement a non animated offset? Add the offset vectors after the time based falloff offset: